Problems and solutions
1).Sticky punching and hanging punching
The fine powder on the surface of the tablet is adhered to by the punch and die during tableting, which makes the surface not smooth, uneven and has dents, and the lettering punch is more prone to sticking and punching. The edge of the hanging edge is rough and grainy. There are several reasons and corresponding countermeasures:
(1) The particles have too much water content, contain hygroscopic and damp-prone drugs, and the operating room temperature and humidity are too high, which is likely to cause stickiness.
Attention should be paid to proper drying, reducing the temperature and humidity in the operating room, and avoiding moisture-inducing drugs from getting wet.
(2) The amount of lubricant is too small or the mixing is uneven, and the fine powder is too much.
The amount of lubricant should be appropriately increased or mixed thoroughly to solve the problem of sticking and punching.
(3) The surface of the punch is not clean, there is anti-rust oil or lubricating oil, the surface of the new die is rough or the lettering is too deep and angular.
The punch can be cleaned, replaced with substandard punches, or rubbed with a small amount of liquid paraffin on the surface of the lettering punch to make the lettering smooth.In addition, if the sticking is caused by mechanical heating, the cause should be checked and the equipment should be overhauled.
(4) The punch and die are too tightly matched to cause hanging punch.
The matching inspection of punching dies should be strengthened to prevent hanging punches.
(5) Some medicines are easy to stick. At the beginning of tablet compression, the pressure can be increased and some lubricants can be appropriately added.
The hot sticking phenomenon of the hair to be punched can be improved.
2)The difference in tablet weight exceeds the limit
The difference in tablet weight exceeding the limit means that the difference in tablet weight exceeds the limit prescribed by the Pharmacopoeia. There are several reasons and corresponding countermeasures:
(1) The particle thickness is unevenly distributed, and the particle flow rate is different during tableting, resulting in the uneven thickness of the particles filled into the die hole, or the difference in thickness is too large.During the blanking, the equipment shakes the coarse and fine layers, so that filling occurs during filling. Large amount of coarse particles.The flakes are light, and the flakes are heavy with more fine particles.
The granules should be mixed well or sieved to remove too much fine powder. If it cannot be resolved, it should be re-granulated.
(2) If there is fine powder sticking to the punch and causing hanging punch, the difference in film weight can be large, and the rotation of the down punch is not flexible at this time.
Check in time, remove the punch, and clean the lower punch and die hole.
(3) The particle fluidity is not good, and the amount of particles flowing into the die hole is sometimes too small, which causes the sheet weight difference to be too large and beyond the limit.
Should re-granulate or add a suitable glidant, such as micro-powder silica gel, to improve the fluidity of the particles.
(4) The feeding hopper is blocked. This phenomenon often occurs when drugs with strong viscous or hygroscopic properties or large lumps of drugs are mixed into particles.
For medicines with strong viscosity or moisture absorption, the feeding hopper should be cleared, the tableting environment should be kept dry, and glidants should be properly added to solve the problem; when large pieces of medicine are mixed into the particles, they should be screened.
(5) The consistency of the punch and the die hole is not good. For example, more powder is leaked between the outer periphery of the lower punch and the die hole wall, which causes the phenomenon of "astringent punching" in the lower punch, resulting in insufficient material filling.
The punch and die ring should be replaced.
(6) The vehicle speed is too fast and the filling volume is insufficient.
The speed of the car should be slowed down.
(7) The length of the upper and lower punches are different, resulting in different fillings.
Find the length of the overshoot or undershoot one by one, and replace it.
(8) The distributor is not installed in place, resulting in uneven packing.
The distributor should be adjusted.